In a steam power plant, heat energy is converted into mechanical energy and ultimately into electrical energy, wherein water steam from the steam generator flows into an expansion machine, such as a steam turbine, wherein the steam is expanded in the steam turbine, with output of work. The steam which flows from the steam turbine is liquefied again in a downstream condenser as a result of heat absorption. The water which is produced in the condenser is delivered again to the steam generator by a feedwater pump, as a result of which a closed circuit is created.
In the operating state, the steam which flows from the steam generator flows into the steam turbine and cools down in the process, wherein the steam pressure reduces. The steam which flows from the steam turbine is fed again to the condenser. During starting, shutting down or in the case of an emergency shutdown of the steam turbine, a live steam valve arranged upstream of the steam turbine is closed and the live steam is directed via a bypass pipeline, wherein the bypass pipeline leads into an exhaust steam pipeline of the steam turbine. The exhaust steam pipeline as a rule is referred to as the cold reheat line if this leads into a reheater, in which the steam is heated to a higher temperature. The higher the steam temperatures are, the higher are the costs for the pipelines, bypass stations and the bypass steam injection to the condenser. Attempts are being undertaken to achieve steam temperatures of about 720° C. Such high temperatures require the use of special materials, such as nickel-based materials. Nickel-based materials are materials with a nickel content of about 40 to 50 per cent by weight. However, such nickel-based materials are comparatively expensive. On the other hand, a nickel-based material can thermally be especially loaded.